You can smile, frown, do all funny face actions thanks to the muscles in your face that contract and relaxes in conjunction to the signals the brain sends. Much to our amazement, many muscles interact with one another just to produce one facial expression.Credit: http://commons.wikimedia.org/wiki/File:Expression_of_the_Emotions_Figure_2.png
The Muscles of Facial Expression
These muscles are generally thin and flat which arise from a facial bone or cartilage and inserts into the dermis of the skin or the fibrous tissue enveloping the sphincter muscles of the orbit or the mouth. The facial muscles are generally arranged into groups according to the place they are located or the region, namely the epicranial group, the orbital group, the nasal group, the oral group and the group of muscles moving the ears. The general function of these muscles is to move the skin wherever they insert.Credit: http://faculty.ucc.edu/biology-potter/musculature/sld002.htm
The Epicranial Muscle
The muscle covering the forehead all the way to the rear of the skull is the epicranial muscle. It is made up of two sections of muscle, the frontalis which covers the forehead and performs actions like raising the eyebrows or actions like wrinkling the forehead. The occiputalis is concern all about the control of the muscles from the back of the skull. An intermediate tendon helps coordinate movements between the frontalis and occiputalis regions. The frontalis is held in place thanks to the help of the facial muscles located above the eyes and nose. On the other hand, the occiputalis is rooted to the occipital bone. Damage to the epicranial muscle can cause an impaired ability to control the eyebrows and the forehead.
The orbicularis oculi is a type of sphincter muscle, tending to close the skin over the eyelids. The orbicularis oculi is the one responsible for blinking movement of the muscles and our ability to draw the eyebrows together or downward. This muscle is a superficial muscle related to expression that encircles the eye. The orbicularis oculi muscle may be divided into the palpebral and orbital parts. With respect to the palpebral parts, it has influence in winking and blinking. The orbital part on the other hand is the muscle that we use to force our eyes to close.Credit: http://www.superstock.com/stock-photos-images/1899-12404
The Nasal Group
The nasal muscle has both compressor and dilator parts, which influences the size of the anterior nasal openings. These muscles are situated deep and can be divided into four categories namely the dilators, compressors, depressors and elevators.Credit: http://face-and-emotion.com/dataface/anatomy/lowerfacemusclesdetails.jsp
The Oral Muscles
Contractions of the cheek muscle buccinator makes possible rapid changes in the volume of the oral cavity. The orbicularis oris is another type of sphincter muscle that tightens the lips. This muscle is the one responsible so that we are able to adjust the opening of our mouth to our desired diameter. The orbicularis oris is capable of making four distinct movements, namely to thrust outward, to roll in between the teeth, to press and tighten and a thinning movement.Credit: http://ideonexus.com/2012/02/12/101-reasons-why-evolution-is-true/
The auricular muscles are the muscles that surround the external ear. There are three auricular muscles namely the anterior, posterior and superior auricular muscles.
Learning the anatomy of the muscles of the face makes us aware of the collaboration of different muscle groups just for us to have expressions. It is vital to understand things in order to get a feel of how important these things are.